Positioning or locking guides for dies



A. F. BAUER POSITIONING OR LOCKING GUIDES FOR DIES 2 Sheets-Sheet 1 7INVENTOR Alfred F. Bauer 1%? Nov. 17, 1959 I Filed Nov. 1, 1956 Maw?? nmm 5 mm (m ww wm Nov. 17, 1959 A. F. BAUER POSITIONING OR LOCKING GUIDESFOR DIES Filed Nov. 1, 1956 2 Sheets-Sheet 2 N am INVENTOR Alfred P.Bauer ORNEY United States Patent O POSITIONING oR LOCKING GUIDES FOR musAlfred F. Bauer, Toledo, Ohio, assignor to National Lead Company, NewYork, N .Y., a corporation of New Jersey Application November 1, 1956,Serial No. 619,754

2 Claims. (Cl. 22-153) This invention relates to a device forpositioning the two sections of a casting die. More specifically, thisinvention relates to a device for positioning and correctly aligning thetwo sections of a die block or permanent mold for producing castingsfrom various materials.

In the production of castings from molten metal by the process ofpressure die casting, two separable sections of a permanent metal die ormold containing the correct impression are used to impart the desiredconfiguration to the finished casting. To obtain the properconfiguration of the die cavity, some means must be employed to insurethe correct alignment of the two separable sections of the die or mold.In order to maintain this alignment, some form of dowell or pin isgenerally used to locate one section in its proper position relative tothe other section. Standard practice in the industry has been toincorporate round dowel pins in one section of the die or mold and around opening usually fitted with a bushing in the mating section. Whenthe metal has been injected the heat flows into the die halves and mayheat them unevenly according to the shape of the cavity. The differentheat conditions between both die halves are often corrected by addingwater cooling systems. However, even the best cooling system does notguarantee uniform heat and temperature conditions in the two die halves.Therefore, they expand differently. On smaller dies this variation fromone half to the other is taken care of by the clearance between dowelpin and bushing. On larger dies, however, this clearance would have tobe so large that too much of a mismatch between one half of the cavityand the other would be encountered.

An attempt to compensate for this unequal expansion between the twosections has been made by positioning the dowels near the center of thedie block. This posi tion for the dowels is undesirable inasmuch as itpermits misalignment of the sections more readily than would positioningthe dowels near the periphery of the die block. The proper positioningof round dowels presents an especially difficult problem when thelongitudinal dimension of the die block greatly exceeds the transversedimension or vice versa.

An object of this invention is to provide a type of positioning devicewhich will assure alignment of die sections even when accompanied by thenatural though unequal expansion of the sections. Another object of thisinvention is to provide a type of positioning device which will not besubject to excessive wear when placed near the periphery of large dieblocks. A further object of this invention is to provide a type ofpositioning device which, in order to assure proper alignment, may bepositioned near the periphery of die blocks whose longitudinal dimensiongreatly exceeds the transverse dimension and whose configuration willnot cause binding, difiiculty of opening or uneven wear of thepositioning device when the segments of the die block are subject tounequal expansion.

These and other objects of this invention will become apparent from thefollowing more complete description and the drawings in which:

Fig. 1 is a face view of a typical holding block for one of theseparable die halves having the guide blocks located at the corners.

Fig. 2 is a perspective view of a portion of two mating die sectionspartially separated.

Fig. 3 is a cross-sectional View of a portion of two mating die sectionsin the closed position.

Fig. 4 is a face view of another holding block for a die, in which thelongitudinal dimension greatly exceeds the lateral, showing an alternatepositioning of the guide members.

The guide members are indicated by the reference numeral 20 in Figs. 1,2 and 3. These guide members have the general shape of right-angledparallelepipeds and are removably mounted in the body of the die orholding block 10 through mounting holes 16 by fastening screws 18 or byother suitable means. A portion of guide member 20 is recessed into thedie body in cavity 12 such that bottom face 27, side faces 26, and backface 28 of the guide member are in juxtaposition respectively to endface 13, side faces 14 and front face 15 of die cavity 12. Theprojecting portion of guide member 20 is provided with mating faces 24which are parallel to each other as well as being parallel to thelongitudinal axis of the guide member and perpendicular to die face 11.The preferred form of guide member 20 has front face '21 parallel to dieface 11 and has a taper surface provided at 22 for ease of mating of theguide memberand guide socket as the die halves are being closed.

The mating portion or guide socket 40 is shown in Figs. 2 and 3 as it isformed in the other die half 60. The sides of guide socket 40 consist ofwear plates 44 which are removably attached into recess 49 by fasteningbolts 50 or other suitable means in such a manner that side face 47 andback face 42 are in juxtaposition respectively to side face 54 and frontface 56 of the recess. Clearance space 51 which permits the movement ofguide member 20 relative to wear plate 44 is formed by the extension ofwear plate 44 into guide cavity 41 beyond inner face 52 of the guidecavity. Guide cavity 41 is formed deep enough into die body 60 thatclearance is provided between back face 43 of the guide socket 40 andfront face 21 of the projecting guide member when the die assembly is inthe closed position. Wear plates 44 are placed so that their inner faces46 are parallel to each other and to the longitudinal axis of the guidesocket 40 as well as being perpendicular to die face 61. Enough space isallowed between faces 46 of the wear plates so as to provide a snug fitbetween the wear faces 46' and mating faces 24 of the projecting guidemember 20 when the die halves are in closed position.

The projecting guide members are normally affixed to that half of thedie which is subject to the greater expansion and are arranged in pairedrelationship the two members of any one pair being located on oppositesides of the die cavity in such manner that an extension of thecenterline of the two guide members forms a straight line. In apreferred embodiment the guide members are positioned on the die face ator near the periphery of the die section.

The guide sockets, also in paired relationship, are formed in the otherdie section being placed in corresponding locations such that when thedie halves are closed to form the enclosed die cavity, the guide membersmatch with and fit into the guide sockets. A snug fit is providedbetween the side faces 24 of the projecting equal to the lateraldimension between wear faces 46 of the guide socket. The longitudinaldimension of the guide socket, i.e. the dimension along the center linepreviously mentioned, however, is larger than is that of the projectingguide member and thus a clearance is provided between bottom face 27 ofthe guide member and the bottom of guide socket 40 so as to permitlongitudinal movement of the projecting guide member relative to thesocket. The term lateral movement refers to movement in a plane parallelto the parting line face of the die sections and in a direction radiallyfrom the center of the die face.

The preferred number of projecting guide members and corresponding guidesockets is four, arranged in two pairs. These guide members may belocated at the four corners as shown in Fig. 1 or intermediate of thecorners as shown in Fig. 4. The latter arrangement is the preferred formonly when the length of the die greatly exceeds the width or vice versa.With either method of locating the guide members, the operation is thesame. The snug fit between the sides of the projecting guide member andthe sides of the mating socket prevents lateral or sideways movement ofthe guide member with respect to the guide socket and vice versa. As aresult, movement of one die half with respect to the other half in anydirection other than radially from the center of the die face isprevented. At the same time, since clearance is provided along thelongitudinal axis of the guide members, i.e. between the ends of theprojecting guide member and its mating socket, movement of any of theguide members relative to its mating socket is possible in a radialdirection from the center of the die face, therefore, permittingexpansion of one die half to be greater than that of the other.

Expansion of a die, caused by heating, is outward from the center in alldirections. By positioning the guide as shown in Figs. 1 or 4, movementof one die relative to the other, which may be caused by the unequalexpansion of the two die halves, is permitted in all directions radiallyfrom the center. At the same time, the configuration of the guidemembers will permit no tangential movement. As a result, the two halvesof the die cavity are kept in perfect alignment and the guide membersare not subject to the excessive strain and Wear which would beencountered if these guide members were the customary round dowels andround holes.

It is understood that the apparatus shown for the accomplishment oflocating or locking two separable die sections in proper alignment withrespect to each other is susceptible to considerable modification.Therefore, the form of the invention described above should beconsidered as illustrative and not limiting the scope of the followingclaims.

I claim:

1.1m combination a die assembly comprising two separable die sectionsforming therebetween, when closed, a die cavity, each of the twoseparable die sections being subject to a different degree of heat witha resultant diiferent amount of radial expansion, and means formaintaining said sections in accurate alignment during closing and whenclosed, said means including at least two projecting guide members ofsubstantially rectangular cross-section positioned in the body of one ofsaid die sections and projecting laterally from the face of saidsection, the projecting guide members being located on opposite sides ofthe die cavity in such a manner that an extension of the centerlines oftwo opposing guide members forms a straight line passing through thecenter of the face of the die section, and at least two matching guidesockets of substantially rectangular cross-section positioned in thebody of the other die section and extending below the face thereof, thelateral dimensions normal to said center line of both the projectingguide members and the guide sockets being substantially identical, thelongitudinal dimension along said center line of the guide socket beinggreater than that of the matching projecting guide member such that asubstantial clearance is provided between the guide member and socketalong the center line, the guide members fitting into the guide socketswhen the die sections are closed.

2. Apparatus according to claim 1 wherein two pairs each of projectingguide members and guide sockets are employed.

References Cited in the file of this patent UNIT ED STATES PATENTS237,619 Smith Feb. 8, 1881 1,082,120 Hanstein Dec. 23, 1913 2,214,998Hogemeyer Sept. 17, 1940 2,218,195 Garrett Oct. 15, 1940 2,319,479 RyderMay 18, 1943 2,456,113 Dorner Dec. 14, 1948 2,530,760 Coulthard Nov. 21,1950 2,572,984 Byers Oct. 30, 1951 FOREIGN PATENTS 4,598 Great BritainMar. 4, 1 901

